1. Field of the Invention
This invention relates to a heat radiation type oil burner, and more particularly to an oil burner adapted to prevent the inner surface of an outermost heat-permeable cylinder from clouding with water vapor or exhaust gas generated during the ignition operation or combustion operation.
2. Description of the Prior Art
In general, a heat radiation type oil burner includes a multiple combustion cylinder construction which comprises red-heated inner and outer cylindrical members and a heat-permeable cylinder arranged to surround the cylindrical members with a space being defined therebetween. In such structure of the oil burner, when water vapor or exhaust gas containing water vapor remains in the space between the outer cylindrical member and the heat-permeable cylinder, the water vapor is liquidified to form fine waterdrops on the inner surface of the heat-permeable cylinder or form white fume to cause clouding of the inner surface of the heat-permeable cylinder to decrease the efficiency of heat radiation of the oil burner.
Such phenomenon frequently appears at the ignition operation during which the heat-permeable cylinder is not yet heated to a high temperature. Such clouding of the heat-permeable cylinder with waterdrops causes a contaminant such as soot, tar or the like contained in the exhaust gas to be absorbed by the waterdrops to stain the inner surface of the heat-permeable cylinder. This results in the efficiency of heat radiation of the oil burner being further decreased, as well as the appearance of the oil burner being injured. Also, it should be noted that such staining cannot be readily removed because it occurs on the inner surface of the heat-permeable cylinder.
Accordingly, it would be highly desirable to develop an oil burner of the heat radiation type which is capable of preventing clouding of the inner surface of a heat-permeable cylinder with moisture and exhaust gas.